Jose is starting an aquarium and has read that the best pH for his fish is around 6.8 He tests his water and finds that his current pH is 7.4 What is the best method to lower his aquarium's pH?

a. Add a large amount of a weak acid to lower the pH quickly
b. Add a weak base a little at a time until the pH is correct
c. Add a large amount of a weak base to lower the pH quickly
d. Add a weak acid a little at a time until the pH is correct